Process for producing ozone



March 30 1926.

Filed Feb. 2. 1925 Walter Inlet ()zonised Air Outlet u J n W. M 4 n M 1% 1% w I5 w m d Q m m m a 1 1 W 60 We fl 1 E E n 1 u r r r 1 n 0 y & e 6 6 k I r p w n M M M B D. Tm M 0 0 P M #M a F W 7 ,p (x t 1411 A M 00 t u l a m m 0 T1 r H MM W W Patented Mar. 30, 1926.

UNITED STATES PATENT 'OFFICE.

ALFRED STARKE, OF SCOTTDALE, PENNSYLVANIA, AND HANS VON WARTENBERG, OF

DANZIG-LANGFUHR, FREE STATE OF DANZIG; ASSIGNORS TO THE FIRM OF OZON- HOCHFREQUENZ, G. M. B, H., OF BERLIN-WILMERSDORF, GERMANY.

PROCESS FOR PRODUCING OZONE.

Application filed February 2, 1923. Serial No. 616,620.

To all whom it may 00-710mm:

Be it known that we, ALFRED STARKE and HANS voN IVARTENBERG, citizens of the Free State of Danzig, and residents, respectively, of Scottdale, in the county of Vestmoreland and State of Pennsylvania, and of Langfuhr, near Danzig, in the Free State of Danzig, have invented certain new and useful Improvements in and Relating to a Process for Producing Ozone; and we do hereby declare the following to be a full, clear, and exact description of the invention, of which the following is a specification.

It has already been proposed to employ for the operation of ozone tubes instead of alternating currents of the usual frequency of 50 per second, alternating currents of higher frequency (see Warburg & Leithauser, Ann. Phys. (4) '01. 28, pp. 15, and 36, 1909'), and it has been found that the use of high frequencies has the advantage that the current load and the efficiency are greater, although it has the drawback that it reduces the maximum yield.

Let A0 denote the maximum yield in ozone (calculated in grammes per kilowatthour) which is attainable for a concentration 0 of ozone and the concentration of the ozone be defined as being the ratio between the quantity of ozone and the quantity of the air subjected to ozonization in the apparatus. It has been found that when use is made of frequencies higher than 50 per second, the maximum yield A0 above referred to is reduced by a value 6 which can only be found empirically, this value being dependent upon the frequency. As this reduction is also dependent upon the concentration, the yield for a particular concentration a is expressed by the formula The formula has been tested up to 500 frequencies per second and the discovery has been utilized in practice, sometimes frequencies up to 700 having been reached. In the absence of experimental data capable of being used to explain the real mechanism of ozonization, it is not possible to say beforehand what the effect would be if the fre quency was considerably increased.

From the empiric data hitherto obtained, it may be expected that the ozone yield per and whether it will only increase up to a maximum and then decrease again.

It has already been proposed to use high frequency currents for producing ozone, the process consisting in employing a condenser connected in parallel with the ozonizer, a sparking gap being interposed between the condenser and the ozonizer, and the circuit being tuned to the desired frequency.

As is well known, such a process produces only damped high frequency oscillations, the frequency being approximately 1 million *per second. The efficiency of this method of producing high frequency currents is naturally very low.

lVe have found by experiments carried out with undamped oscillations that a tube consuming 1 watt at 50 periods, could be loaded with '30 watts at 4000 periods, and with 100 watts at 8000 periods, without increasing the initial voltage and without the ozone yield dropping below the initial .amount of about 200 grammes of ozone per kw. hr. obtained from oxygen. That is to say, the ozonization could be carried out with a frequency 160 times higher than that of the usual frequency of 50 to obtain the same out put in an apparatus which is one hundred times smaller. A similar result was also-obtained with larger tubes; in that case the temperature of the air or oxygen treated was suitably reduced by intensive cooling. In practice it is preferable to use higher frequencies than those above referred to, viz, betlween 10,000 and 100,000 periods per secon These experiments have shown that tubes constructed in the usual manner, irrespective of whether one or both electrodes is or are made of glass, have the drawback that they are perforated in the case of a high load; in actual practice, frequently even in thecase of a. moderate load.

A powerful edge action (creeping sparks, silent discharges) and consequently heating and destruction of the glass, takes place at the ends of the electrodes. This drawback may be avoided without impairing the work ing of the apparatus by thickening the dielectric at the edges of the solid dielectric, and by increasing the thickness of the layer put of the ozonizer.

of gas, this thickening being efl'ected within. the cooling zone, and

The accompanying drawing illustrates one form of apparatus for carrying the present invention into effect.

The ozonizer comprises three concentric chambers separated from one another and provided with the Corresponding inlets and outlets.

5 is the inner electrode which consists in a known manner of a tube of glass or like material capable of acting as a dielectric and of a wire coil or wire netting carried by the said tube. This form of construction of electrodes being well known, it is not considered necessary to illustrate the actual construction. Water is caused to flow through the electrode 5 which forthis purpose is provided with an inlet 7 and an outlet 11 is the outer electrode which similarly consists of a glass or like tube and of a wire coil or wire netting provided thereon. Phe outer and the inner electrode thus enclose a cylindrical space 6 which is provided with an inlet 8 and an outlet 10. The glass tubes of the two electrodes are preferably fused together at the lower and upper ends.

1 is a cylinder preferably of glass which surrounds the upper electrode and is closed up by packings 13 and 14 which make a tight joint with the electrode tubes. 2 is a water inlet and 3 a water outlet provided for the annular chamber 12 which is formed between the outer el'ectrode 11 and the cylinder 1.

During the operation of the ozonizer, water which is in electrical connection with the one pole of the source of electricity is admitted through the pipe 2 whilst water, which is in electrical connection with the other pole of the source of electricity is admitted through the pipe 7 to the annular chamber 12 and the hollow space of the elec- .quency currents.

1 trodes outwardly and inwardly respectively,

in order to increase the electric resistance at these points,and'we wish it to be understood that the ozonizer according to the present in vention is limited to its use with high frequency currents between,10,000 and 100,000 periods per second and in combination with means for ensuring that the ends of both electrodes shall be subjected to a cooling action that is sufficiently strong for high fre- What we claim isz Q 1. In a process for producing ozone in an ozonizer having electrodes, which consists in passing the medium tobe ozonized through the ozonizer betweenthe electrodes and sub- 'jecting it therein to'the action of electric energydn the form of alternating currents, supplying the. alternating currents to the said electrodes in the form of un'damped oscillations, the periodicities of which lie in the range from 1,000 to 100,000 periods per second as set forth.

2. An ozonizer for the electric production of ozone by means of high frequency alternating currents comprising a tubular elcctrode, another tubular electrode surrounding the same in combination with a dielectric between the said electrodes the dielectric being thicker at the ends of the electrodes as compared with its portion between the ends thereof and the said electrodes being capable of exertingat the said ends where the thickor dielectric is provided, a strong cooling action as regards high frequency currents. In testimony whereof we have signed our names to this specification.

ALFRED STARKE. I HANS VON VVARTENBERG. 

